California Partners for Advanced Transportation Technology

In this report, the authors describe preliminary research dealing with vehicle emissions associated directly with 1) Automated Highway Systems ( AHS) and 2) ramp metering. In performing this analysis, a power-demand modal emissions model has been integrated with several transportation simulation models in order to quantitatively determine the effects of Intelligent Transportation Systems (ITS) technology on vehicle emissions. For AHS, a steady-state speed/emissions comparison has been conducted between vehicles that are platooned and non-platooned. A comparison has been made between a platoon under optimized and non-optimized CICC ( Coordinated Intelligent Cruise Control) and AICC (Autonomous Intelligent Cruise Control) control laws. For ramp metering, an initial evaluation has been conducted concentrating on the effect of vehicle emissions. Three components of ramp metering were evaluated independently: 1) the effect of freeway traffic smoothing, 2) ramp and surface street congestion, and 3) hard accelerations from the ramp meters.